INTERNATIONAL TELECOMMUNICATION UNION
ITU-T
TELECOMMUNICATION
STANDARDIZATION SECTOR
OF ITU
X.692
Amendment 1
(08/2004)
SERIES X: DATA NETWORKS AND OPEN SYSTEM
COMMUNICATIONS
OSI networking and system aspects – Abstract Syntax
Notation One (ASN.1)
Information technology – ASN.1 encoding rules:
Specification of Encoding Control Notation (ECN)
Amendment 1: Extensibility support
ITU-T Recommendation X.692 (2002) – Amendment 1
ITU-T X-SERIES RECOMMENDATIONS
DATA NETWORKS AND OPEN SYSTEM COMMUNICATIONS
PUBLIC DATA NETWORKS
Services and facilities
Interfaces
Transmission, signalling and switching
Network aspects
Maintenance
Administrative arrangements
OPEN SYSTEMS INTERCONNECTION
Model and notation
Service definitions
Connection-mode protocol specifications
Connectionless-mode protocol specifications
PICS proformas
Protocol Identification
Security Protocols
Layer Managed Objects
Conformance testing
INTERWORKING BETWEEN NETWORKS
General
Satellite data transmission systems
IP-based networks
MESSAGE HANDLING SYSTEMS
DIRECTORY
OSI NETWORKING AND SYSTEM ASPECTS
Networking
Efficiency
Quality of service
Naming, Addressing and Registration
Abstract Syntax Notation One (ASN.1)
OSI MANAGEMENT
Systems Management framework and architecture
Management Communication Service and Protocol
Structure of Management Information
Management functions and ODMA functions
SECURITY
OSI APPLICATIONS
Commitment, Concurrency and Recovery
Transaction processing
Remote operations
OPEN DISTRIBUTED PROCESSING
TELECOMMUNICATION SECURITY
For further details, please refer to the list of ITU-T Recommendations.
X.1–X.19
X.20–X.49
X.50–X.89
X.90–X.149
X.150–X.179
X.180–X.199
X.200–X.209
X.210–X.219
X.220–X.229
X.230–X.239
X.240–X.259
X.260–X.269
X.270–X.279
X.280–X.289
X.290–X.299
X.300–X.349
X.350–X.369
X.370–X.399
X.400–X.499
X.500–X.599
X.600–X.629
X.630–X.639
X.640–X.649
X.650–X.679
X.680–X.699
X.700–X.709
X.710–X.719
X.720–X.729
X.730–X.799
X.800–X.849
X.850–X.859
X.860–X.879
X.880–X.899
X.900–X.999
X.1000–
INTERNATIONAL STANDARD ISO/IEC 8825-3
ITU-T RECOMMENDATION X.692
Information technology – ASN.1 encoding rules: Specification of Encoding
Control Notation (ECN)
Amendment 1
Extensibility support
Summary
This amendment adds the capability to use ECN to specify the way in which open types are encoded. It also adds support
for enhancement of the "conditions" mechanism, allowing more complex conditions to be expressed.
Source
Amendment 1 to ITU-T Recommendation X.692 (2002) was approved on 29 August 2004 by ITU-T Study Group 17
(2001-2004) under the ITU-T Recommendation A.8 procedure. An identical text is also published as ISO/IEC 8825-3,
Amendment 1.
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
i
FOREWORD
The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of
telecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of
ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing
Recommendations on them with a view to standardizing telecommunications on a worldwide basis.
The World Telecommunication Standardization Assembly (WTSA), which meets every four years,
establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on
these topics.
The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1.
In some areas of information technology which fall within ITU-T's purview, the necessary standards are
prepared on a collaborative basis with ISO and IEC.
NOTE
In this Recommendation, the expression "Administration" is used for conciseness to indicate both a
telecommunication administration and a recognized operating agency.
Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain
mandatory provisions (to ensure e.g. interoperability or applicability) and compliance with the
Recommendation is achieved when all of these mandatory provisions are met. The words "shall" or some
other obligatory language such as "must" and the negative equivalents are used to express requirements. The
use of such words does not suggest that compliance with the Recommendation is required of any party.
INTELLECTUAL PROPERTY RIGHTS
ITU draws attention to the possibility that the practice or implementation of this Recommendation may
involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence,
validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others
outside of the Recommendation development process.
As of the date of approval of this Recommendation, ITU had not received notice of intellectual property,
protected by patents, which may be required to implement this Recommendation. However, implementors
are cautioned that this may not represent the latest information and are therefore strongly urged to consult the
TSB patent database.
 ITU 2005
All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the
prior written permission of ITU.
ii
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
CONTENTS
Page
1
Subclause 3.2.8...............................................................................................................................................
1
2
New subclauses 9.25 bis and 9.25 ter.............................................................................................................
9.25 bis
Other conditions for applying encodings ..............................................................................
9.25 ter
Encoding control for the open type .......................................................................................
1
1
1
3
Subclause 13.2.9.............................................................................................................................................
2
4
Subclause 13.2.10.5........................................................................................................................................
2
5
Subclause 17.5.15...........................................................................................................................................
2
6
Subclause 18.2.6.............................................................................................................................................
3
7
Subclause 21.11.1...........................................................................................................................................
3
8
Subclause 21.11.4...........................................................................................................................................
3
9
New subclause 21.11.5 ...................................................................................................................................
4
10
New subclause 21.11 bis ................................................................................................................................
21.11 bis
The Comparison type.......................................................................................................
4
4
11
Subclause 21.12.1...........................................................................................................................................
4
12
Subclause 21.12.4...........................................................................................................................................
5
13
New subclause 21.12.5 ...................................................................................................................................
5
14
New subclause 21.16......................................................................................................................................
21.16 The IntegerMapping type ............................................................................................................
5
5
15
Subclause 23.2.3.8..........................................................................................................................................
5
16
Subclause 23.4.3.8..........................................................................................................................................
5
17
Subclause 23.6.2.3..........................................................................................................................................
5
18
Subclause 23.7.1.............................................................................................................................................
6
19
Subclause 23.7.2.2..........................................................................................................................................
7
20
Subclause 23.7.2.4..........................................................................................................................................
8
21
Subclauses 23.7.2.6, 23.7.2.7 and 23.7.2.8.....................................................................................................
8
22
Subclause 23.9.3.8..........................................................................................................................................
8
23
New subclause 23.9 bis ..................................................................................................................................
23.9 bis
Defining encoding objects for classes in the open type category..........................................
8
8
24
Subclause 23.12.2.3........................................................................................................................................
11
25
Subclause 23.13.1...........................................................................................................................................
23.13.1 The defined syntax ................................................................................................................
11
11
26
Subclauses 23.13.2.1 and 23.13.2.2................................................................................................................
13
27
Subclause 23.15..............................................................................................................................................
23.15 Defining encoding objects for classes in the other categories.............................................................
13
13
28
Subclause 24.3.1.............................................................................................................................................
13
29
New subclause 24.3.2 bis ...............................................................................................................................
13
30
New subclause 24.3.8 bis ...............................................................................................................................
13
31
Table 6............................................................................................................................................................
14
32
Subclause C.1 .................................................................................................................................................
14
33
Subclause C.4 .................................................................................................................................................
14
34
Subclause G.2.4..............................................................................................................................................
15
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
iii
ISO/IEC 8825-3:2002/Amd.1:2005 (E)
INTERNATIONAL STANDARD
ITU-T RECOMMENDATION
Information technology –
ASN.1 encoding rules:
Specification of Encoding Control Notation (ECN)
Amendment 1
Extensibility support
NOTE – All new or changed text in this amendment is underlined in clauses being replaced. When new clauses with a heading
are inserted, only the heading is underlined. Deleted text is present but marked with a strike-through. When merging all such text
into the base Recommendation | International standard, the underlining is to be removed and struck-through text taken out.
1
Subclause 3.2.8
Replace 3.2.8 with:
3.2.8
conditional encoding: An encoding which is to be applied only if some specified condition bounds condition
or size range condition is satisfied.
NOTE – The condition may be a bounds condition or a size range condition, or other more complex conditions.
2
New subclauses 9.25 bis and 9.25 ter
Insert new clauses 9.25 bis and 9.25 ter and update the contents:
9.25 bis Other conditions for applying encodings
9.25 bis.1 There are a number of different conditions that can be tested in order to select an appropriate encoding. These
include the actual value and the range of bounds.
9.25 bis.2 It is also possible to require that all of a given list of conditions are to be satisfied.
9.25 bis.3 A test for a condition uses either a single enumeration value (such as "bounded-without-negatives")
which contains the entire test in the specification of the one enumeration, or a triple of enumerations.
9.25 bis.4 If a triple is used, the first identifies (by an enumeration) the item that is being tested (for example
"test-upper-bound"), the second is the nature of the test (for example "greater-than"), and the third provides an
integer value for the test.
9.25 ter Encoding control for the open type
9.25 ter.1 Open types frequently provide a means of extensibility using an identification field, with new values for the
identification field and new types for the open type being added in successive versions (and often being available for
vendor-specific extensions).
9.25 ter.2 Both these features mean that a decoder may be asked to decode an open type when that particular
implementation has no knowledge of the type that has been encoded into it.
9.25 ter.3 The encoding support provided for the open type is the same as that for most other classes in the bitfield
category, but with the added ability to specify that a different encoding object set is to be applied to the type which is to
be encoded into the open type.
NOTE – This is in recognition that many protocols choose to use a different style of encoding (often based on a type-length-value
approach) for the type contained in an open type, while retaining a more compact style of encoding for the fields of the message
containing the open type.
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
1
ISO/IEC 8825-3:2002/Amd.1:2005 (E)
9.25 ter.4 The model used for decoding an open type recognizes that a decoder will not know what type fills the open
type (table and relational constraints are not visible to either PER or to ECN), but that the application may be able to
determine this from some other field in the protocol, or in a previous message, or (for vendor-specific additions) based
on calling address.
9.25 ter.5 The model is therefore that, having dealt with any specified pre-padding, and determined the encoding space
and any value pre- and post-padding, the decoder will ask the application for the type which has been encoded. (In the
case of tools, the application will almost certainly have pre-configured the tool with a list of the known types that might
be present, and would simply return a pointer to one of these.) Decoding can now proceed normally.
9.25 ter.6 The application may, however, say "unknown" (see 9.25 ter.4), and the decoder then needs to know how to
determine the end of this unknown encoding. This is satisfied by enabling the ECN specifier in this case to provide an
encoding structure, and (optionally) an encoding object set to use with it, which is to be used by decoders for decoding
unknown types in the open type. There is syntax provided in clause 23 for this purpose.
NOTE – An example of such an encoding structure could be one that specifies an encoding that is commonly known as a "Type,
Length, Value" encoding, whose end can be determined without knowledge of the type being encoded.
3
Subclause 13.2.9
Replace subclause 13.2.9 with:
13.2.9
4
At later stages in these procedures, the application point may be on any of the following:
a)
An encoding class name. This is completely encodable using the specification in an encoding object of
the same class (see 17.1.7).
b)
An encoding constructor (see 16.2.12). The construction procedures can be determined by the
specification contained in an encoding object of the encoding constructor class, but that encoding object
does not determine the encoding of the components. The specification of the encoding object that is
applied may require that one or more of the components of the constructor are replaced by other
(parameterized) structures before the application point passes to the components.
c)
A class in the bitstring or octetstring category that has a contained type as a property associated with the
values (see 11.3.4.3 d). The encoding of the contained type depends on whether there is an ENCODED BY
present, and on the specification of the encoding object being applied (see 22.11).
d)
A class in the open type category. The encoding of the component of the open type depends on whether
there is an ENCODED WITH present, and on the specification of the encoding object being applied (see
23.9 bis.2).
e)
A component which is an encoding class (possibly preceded by one or more classes in the tag category),
followed by an encoding class in the optionality category. The procedures and encodings for determining
presence or absence are determined by the specification contained in an encoding object of the class in
the optionality category. This encoding object may also require the replacement of the encoding class
(together with all its preceding classes in the tag category) with a (parameterized) replacement structure
before that class is encoded. The application point then passes to the first class in the tag category
(if any), or to the component, or to its replacement.
f)
An encoding class preceded by an encoding class in the tag category. The tag number associated with the
class in the tag category is encoded using the specification in an encoding object of the class in the tag
category, and the application point then passes to the tagged class.
g)
Any other built-in encoding class. This is completely encodable using the specification contained in an
encoding object of that class.
Subclause 13.2.10.5
Replace the Note in 13.2.10.5 with:
NOTE – If the encoding object being applied to a class in the open type category contains an ENCODED WITH, this determines
the encoding object set that is applied to the component, otherwise the combined encoding object set that is being applied to this
class is applied to the component (see 23.9 bis.2).
5
Subclause 17.5.15
Replace 17.5.15 with:
2
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
ISO/IEC 8825-3:2002/Amd.1:2005 (E)
17.5.15 If a REFERENCE is needed as an actual parameter of any of the encoding objects or encoding object sets used
in this production, then it can either be supplied as a dummy parameter of the encoding object that is being defined, or it
can be supplied as a "ComponentIdList" (see 15.3.1 for the syntax of the "ComponentIdList" – the meaning of the
"ComponentIdList" in this context is specified below).
17.5.15 bis
If the governor is not a constructor in the repetition category, then the first (or only) "identifier" in the
"ComponentIdList" shall be the "identifier" of a textually present "NamedType" (at some level of nesting – see
17.5.15 ter) of the construction that is obtained by de-referencing the governor. It identifies the entire definition of that
"NamedType" component, whether that definition is textually present or not.
17.5.15 ter
If there is more than one such matching identifier, then the chosen matching identifier shall be
determined by the first match in a scan (in textual order) of the outer-level identifiers, then by a scan (in textual order)
of the second level identifiers, then by a scan (in textual order) of the third-level identifiers, and so on.
17.5.15 quat Each subsequent "identifier" of the "ComponentIdList" (if any) shall be an "identifier" in a
"NamedType" of the structure identified by the previous part of the "ComponentIdList", and identifies the entire
definition of that "NamedType" component, whether it is textually present or not in the definition of the structure
identified by the previous part of the "ComponentIdList".
17.5.15 quin If the governor is a constructor in the repetition category, then the actual parameter for the REFERENCE
shall be a "ComponentIdList" whose first "identifier" identifies a component that is textually present in the
"EncodingStructure" in the "RepetitionStructure" obtained by de-referencing the repetition (see 17.5.15 ter). Subclauses
17.5.15 ter and 17.5.15 quat then apply.
17.5.15 sex
If the REFERENCE is required to identify a container, it can also be supplied as:
a)
STRUCTURE (provided the constructor for the structure being encoded is not an alternatives category)
when it refers to that structure;
b)
OUTER when it refers to the container of the complete encoding.
NOTE – The "EncodeStructure" is the only production in which REFERENCEs can be supplied, except through the use of
dummy parameters or the use of OUTER, or where references are in support of flag-to-be-used or flag-to-be-set in
the definition of an encoding object for a class in the repetition category which uses replacement.
6
Subclause 18.2.6
Replace the Note in 18.2.6 with:
NOTE – The combined encoding object set applied by these encoding objects to the type chosen for use with the #OPEN-TYPE
class is always the same as the combined encoding object set applied to the #OPEN-TYPE class as these encoding objects do not
contain an ENCODED WITH (see 13.2.10.5 and 13.2.9 d).
7
Subclause 21.11.1
Replace 21.11.1 with:
21.11.1 The "RangeCondition" type is:
RangeCondition ::= ENUMERATED
{unbounded-or-no-lower-bound,
semi-bounded-with-negatives,
bounded-with-negatives,
semi-bounded-without-negatives,
bounded-without-negatives,
test-lower-bound,
test-upper-bound,
test-range}
8
Subclause 21.11.4
Replace 21.11.4 with:
21.11.4 The predicate is satisfied for each of the first five enumeration values of 21.11.1 if and only if the following
conditions are satisfied by the bounds on the encoding class in the integer category:
a)
unbounded-or-no-lower-bound: either there are no bounds, or else there is only an upper bound but
no lower bound.
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
3
ISO/IEC 8825-3:2002/Amd.1:2005 (E)
b)
semi-bounded-with-negatives: there is a lower bound that is less than zero, but no upper bound.
c)
bounded-with-negatives: there is a lower bound that is less than zero, and an upper bound.
d)
semi-bounded-without-negatives: there is a lower bound that is greater than or equal to zero, but
no upper bound.
e)
bounded-without-negatives: there is a lower bound that is greater than or equal to zero, and an
upper bound.
NOTE – For any given set of bounds, exactly one predicate will be satisfied.
9
New subclause 21.11.5
Add a new subclause 21.11.5:
21.11.5 If the last three enumeration values of 21.11.1 are used, a value of the "Comparison" type (see 21.11 bis)
shall be provided, together with an integer comparator value. If the other enumeration values are used, these shall not
be provided.
10
New subclause 21.11 bis
Add a new subclause 21.11 bis after 21.11 and add to the contents list:
21.11 bis
The Comparison type
21.11 bis.1
The "Comparison" type is:
Comparison ::= ENUMERATED
{equal-to,
not-equal-to,
greater-than,
less-than,
greater-than-or-equal-to,
less-than-or-equal-to}
21.11 bis.2
There is no default value for an encoding property of this type.
21.11 bis.3
An encoding property of type "Comparison" is used to test an identified property of a class against an
integer value (the comparator).
21.11 bis.4
The predicate using a "Comparison" is satisfied for each enumeration value if and only if the identified
property satisfies the following conditions:
a)
equal-to: its value equals that of the specified integer comparator value.
b)
not-equal-to: its value is different from that of the specified integer comparator value.
c)
greater-than: its value is greater than that of the specified integer comparator value.
d)
less-than: its value is less than that of the specified integer comparator value.
e)
greater-than-or-equal-to: its value is greater than or equal to that of the specified integer
comparator value.
f)
less-than-or-equal-to: its value is less than or equal to that of the specified integer comparator
value.
11
Subclause 21.12.1
Replace 21.12.1 with:
21.12.1 The "SizeRangeCondition" type is:
SizeRangeCondition ::= ENUMERATED
{no-ub-with-zero-lb,
ub-with-zero-lb,
no-ub-with-non-zero-lb,
ub-with-non-zero-lb,
fixed-size,
4
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
ISO/IEC 8825-3:2002/Amd.1:2005 (E)
test-lower-bound,
test-upper-bound,
test-range}
12
Subclause 21.12.4
Replace 21.12.4 with:
21.12.4 The predicate is satisfied for each of the first five enumeration values of 21.12.1 if and only if the effective
size constraint satisfies the following conditions:
a)
no-ub-with-zero-lb: there is no upper bound on the size and the lower bound is zero.
b)
ub-with-zero-lb: there is an upper bound on the size and the lower bound is zero.
c)
no-ub-with-non-zero-lb: there is no upper bound on the size and the lower bound is non-zero.
d)
ub-with-non-zero-lb: there is an upper bound on the size and the lower bound is non-zero.
e)
fixed-size: the lower bound and the upper bound on the size are the same value.
NOTE – Only the "fixed-size" case overlaps with other predicates.
13
New subclause 21.12.5
Add a new subclause 21.12.5 after 21.12.4:
21.12.5 If the last three enumeration values of 21.12.1 are used, a value of the "Comparison" type (see 21.11 bis)
shall be provided, together with an integer comparator value. If the other enumeration values are used, these shall not
be provided.
14
New subclause 21.16
Add a new subclause 21.16:
21.16
The IntegerMapping type
21.16.1 The "IntegerMapping" type is:
IntegerMapping ::= SET OF SEQUENCE {
source SET OF INTEGER,
result INTEGER} (CONSTRAINED BY {/* the intersection of the source
components shall be empty */})
21.16.2 The "IntegerMapping" is used to specify explicitly an ints-to-ints transform.
15
Subclause 23.2.3.8
Replace 23.2.3.8 with:
23.2.3.8 If an encoding object in the "REPETITION-ENCODINGS" ordered list is defined using "IF" or "IF-ALL", then
all preceding encoding objects in that list shall be defined using "IF" or "IF-ALL".
16
Subclause 23.4.3.8
Replace 23.4.3.8 with:
23.4.3.8 If an encoding object in the "REPETITION-ENCODINGS" ordered list is defined using "IF" or "IF-ALL", then
all preceding encoding objects in that list shall be defined using "IF" or "IF-ALL".
17
Subclause 23.6.2.3
Replace 23.6.2.3 with:
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
5
ISO/IEC 8825-3:2002/Amd.1:2005 (E)
23.6.2.3 If an encoding object in the "ENCODINGS" ordered list is defined using "IF" or "IF-ALL", then all preceding
encoding objects in that list shall be defined using "IF" or "IF-ALL".
18
Subclause 23.7.1
Replace 23.7.1 with:
23.7.1
The defined syntax
The syntax for defining encoding objects for the #CONDITIONAL-INT class is defined as:
#CONDITIONAL-INT ::= ENCODING-CLASS {
-- Condition (see 21.11)
&range-condition
&comparison
&comparator
&Range-conditions
&Comparisons
&Comparators
RangeCondition OPTIONAL,
Comparison OPTIONAL,
INTEGER OPTIONAL,
RangeCondition ORDERED OPTIONAL,
Comparison ORDERED OPTIONAL,
INTEGER ORDERED OPTIONAL,
-- Structure-only replacement specification (see 22.1)
&#Replacement-structure
OPTIONAL,
&replacement-structure-encoding-object &#Replacement-structure OPTIONAL,
-- Pre-alignment and padding specification (see 22.2)
&encoding-space-pre-alignment-unit Unit (ALL EXCEPT repetitions)
DEFAULT bit,
&encoding-space-pre-padding
Padding DEFAULT zero,
&encoding-space-pre-pattern
Non-Null-Pattern (ALL EXCEPT
different:any) DEFAULT bits:'0'B,
-- Start pointer specification (see 22.3)
&start-pointer
REFERENCE
OPTIONAL,
&start-pointer-unit
Unit (ALL EXCEPT repetitions)
DEFAULT bit,
&Start-pointer-encoder-transforms #TRANSFORM ORDERED OPTIONAL,
-- Encoding space specification (see 22.4)
&encoding-space-size
EncodingSpaceSize
DEFAULT self-delimiting-values,
&encoding-space-unit
Unit (ALL EXCEPT repetitions)
DEFAULT bit,
&encoding-space-determination
EncodingSpaceDetermination
DEFAULT field-to-be-set,
&encoding-space-reference
REFERENCE OPTIONAL,
&Encoder-transforms
#TRANSFORM ORDERED OPTIONAL,
&Decoder-transforms
#TRANSFORM ORDERED OPTIONAL,
-- Value encoding
&Transform
&encoding
#TRANSFORM ORDERED OPTIONAL,
ENUMERATED
{positive-int, twos-complement,
reverse-positive-int,
reverse-twos-complement}
DEFAULT twos-complement,
-- Value padding and justification (see 22.8)
&value-justification
Justification DEFAULT right:0,
&value-pre-padding
Padding DEFAULT zero,
&value-pre-pattern
Non-Null-Pattern DEFAULT bits:'0'B,
&value-post-padding
Padding DEFAULT zero,
&value-post-pattern
Non-Null-Pattern DEFAULT bits:'0'B,
&unused-bits-determination
UnusedBitsDetermination
DEFAULT field-to-be-set,
&unused-bits-reference
REFERENCE OPTIONAL,
&Unused-bits-encoder-transforms
#TRANSFORM ORDERED OPTIONAL,
&Unused-bits-decoder-transforms
#TRANSFORM ORDERED OPTIONAL,
-- Identification handle specification (see 22.9)
6
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
ISO/IEC 8825-3:2002/Amd.1:2005 (E)
&exhibited-handle
&Handle-positions
&Handle-value
PrintableString OPTIONAL,
INTEGER (0..MAX) OPTIONAL,
HandleValue DEFAULT tag:any,
-- Bit reversal specification (see 22.12)
&bit-reversal
ReversalSpecification
DEFAULT no-reversal
}
WITH SYNTAX {
[IF &range-condition [&comparison &comparator]]
[IF-ALL &Range-conditions [&Comparisons &Comparators]]
[ELSE]
[REPLACE
[STRUCTURE]
WITH &#Replacement-structure
[ENCODED BY &replacement-structure-encoding-object]]
[ALIGNED TO
[NEXT]
[ANY]
&encoding-space-pre-alignment-unit
[PADDING &encoding-space-pre-padding
[PATTERN &encoding-space-pre-pattern]]]
[START-POINTER
&start-pointer
[MULTIPLE OF
&start-pointer-unit]
[ENCODER-TRANSFORMS
&Start-pointer-encoder-transforms]]
ENCODING-SPACE
[SIZE &encoding-space-size
[MULTIPLE OF &encoding-space-unit]]
[DETERMINED BY &encoding-space-determination]
[USING &encoding-space-reference
[ENCODER-TRANSFORMS &Encoder-transforms]
[DECODER-TRANSFORMS &Decoder-transforms]]
[TRANSFORMS &Transforms]
[ENCODING &encoding]
[VALUE-PADDING
[JUSTIFIED &value-justification]
[PRE-PADDING &value-pre-padding
[PATTERN &value-pre-pattern]]
[POST-PADDING &value-post-padding
[PATTERN &value-post-pattern]]
[UNUSED BITS
[DETERMINED BY &unused-bits-determination]
[USING &unused-bits-reference
[ENCODER-TRANSFORMS &Unused-bits-encoder-transforms]
[DECODER-TRANSFORMS &Unused-bits-decoder-transforms]]]]
[EXHIBITS HANDLE &exhibited-handle AT &Handle-positions
[AS &handle-value]]
[BIT-REVERSAL &bit-reversal]
}
19
Subclause 23.7.2.2
Replace 23.7.2.2 with:
23.7.2.2 The syntax allows the specification of a single condition on the bounds of the integer for this encoding to be
applied (use of "IF"). It also allows the specification that all of a set of conditions are to be satisfied (use of "IF-ALL").
It also allows the specification that there is no condition. The use of "ELSE", or omission of both "IF", "IF-ALL" and
"ELSE" specifies that there is no condition. "IF-ALL" shall be used with three lists if one or more of the
size-range-conditions require a comparison, and shall be used with one list otherwise. When using three lists,
size-range-conditions that do not require a comparison or comparator (if any) shall follow all those that require a
comparison, and shall have no corresponding entry in the second and third lists. In using "IF-ALL" with three lists, the
lists shall be interpreted as a list of predicates using the values in corresponding positions in the three lists.
NOTE – It is recommended that the three lists be formatted to provide a condition in each column.
EXAMPLE:
IF-ALL {test-lower-bound, test-range
, bounded-with-negatives }
{greater-than
, less-than-or-equal-to }
{-10
, 20
}
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
7
ISO/IEC 8825-3:2002/Amd.1:2005 (E)
20
Subclause 23.7.2.4
Replace 23.7.2.4 with:
23.7.2.4 At most one of "IF", "IF-ALL" and "ELSE" shall be present.
21
Subclauses 23.7.2.6, 23.7.2.7 and 23.7.2.8
Replace 23.7.2.6, 23.7.2.7 and 23.7.2.8 with:
23.7.2.6 It is an ECN specification or application error if any transform in the "TRANSFORMS" is not reversible for the
abstract value to which it is applied. The first transform of "TRANSFORMS", if present, shall have a source that is integer
and the last transform shall have a result that is integer.
NOTE – The tests for the "IF" and "IF-ALL" conditions takes place on the bounds of the original value, and areis not affected
by these transforms.
23.7.2.7 The "INT-TO-INT" transform with the value "subtract:lower-bound" shall be included only if the "IF"
or "IF-ALL" condition restricts the application of this encoding to classes of the integer category with a lower bound,
and (if present) shall be the first transform in the list.
23.7.2.8 The "ENCODING-SPACE SIZE" shall not be "fixed-to-max" unless the "IF" or "IF-ALL" condition restricts
the encoding to a class with both an upper and a lower bound.
22
Subclause 23.9.3.8
Replace 23.9.3.8 with:
23.9.3.8 If an encoding object in the "REPETITION-ENCODINGS" ordered list is defined using "IF" or "IF-ALL", then
all preceding encoding objects in that list shall be defined using "IF" or "IF-ALL".
23
New subclause 23.9 bis
Insert the new subclause 23.9 bis after 23.9 and update the contents:
23.9 bis Defining encoding objects for classes in the open type category
23.9 bis.1 The defined syntax
The syntax for defining encoding objects for classes in the open type category is defined as:
#OPEN-TYPE ::= ENCODING-CLASS {
-- Structure-only replacement specification (see 22.1)
&#Replacement-structure
OPTIONAL,
&replacement-structure-encoding-object
&#Replacement-structure OPTIONAL,
-- Pre-alignment and padding specification (see 22.2)
&encoding-space-pre-alignment-unit
Unit (ALL EXCEPT repetitions)
DEFAULT bit,
&encoding-space-pre-padding
Padding DEFAULT zero,
&encoding-space-pre-pattern
Non-Null-Pattern (ALL EXCEPT different:any)
DEFAULT bits:'0'B,
-- Start pointer specification (see 22.3)
&start-pointer
REFERENCE OPTIONAL,
&start-pointer-unit
Unit (ALL EXCEPT repetitions) DEFAULT bit,
&Start-pointer-encoder-transforms #TRANSFORM ORDERED OPTIONAL,
-- Encoding space specification (see 22.4)
&encoding-space-size
EncodingSpaceSize
DEFAULT self-delimiting-values,
&encoding-space-unit
Unit (ALL EXCEPT repetitions)
DEFAULT bit,
&encoding-space-determination
EncodingSpaceDetermination
8
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
ISO/IEC 8825-3:2002/Amd.1:2005 (E)
&encoding-space-reference
&Encoder-transforms
&Decoder-transforms
DEFAULT field-to-be-set,
REFERENCE OPTIONAL,
#TRANSFORM ORDERED OPTIONAL,
#TRANSFORM ORDERED OPTIONAL,
-- Open-type encoding
&Known-structure-encodings
&Unknown-structure
&Unknown-structure-encodings
#ENCODINGS OPTIONAL,
OPTIONAL,
#ENCODINGS OPTIONAL,
-- Value padding and justification (see 22.8)
&value-justification
Justification DEFAULT right:0,
&value-pre-padding
Padding DEFAULT zero,
&value-pre-pattern
Non-Null-Pattern DEFAULT bits:'0'B,
&value-post-padding
Padding DEFAULT zero,
&value-post-pattern
Non-Null-Pattern DEFAULT bits:'0'B,
&unused-bits-determination
UnusedBitsDetermination
DEFAULT field-to-be-set,
&unused-bits-reference
REFERENCE OPTIONAL,
&Unused-bits-encoder-transforms
#TRANSFORM ORDERED OPTIONAL,
&Unused-bits-decoder-transforms
#TRANSFORM ORDERED OPTIONAL,
-- Bit reversal specification (see 22.12)
&bit-reversal
ReversalSpecification
DEFAULT no-reversal
}
WITH SYNTAX {
[REPLACE
[STRUCTURE]
WITH &#Replacement-structure
[ENCODED BY &replacement-structure-encoding-object]]
[ALIGNED TO
[NEXT]
[ANY]
&encoding-space-pre-alignment-unit
[PADDING &encoding-space-pre-padding
[PATTERN &encoding-space-pre-pattern]]]
[START-POINTER &start-pointer
[MULTIPLE OF
&start-pointer-unit]
[ENCODER-TRANSFORMS
&Start-pointer-encoder-transforms]]
ENCODING-SPACE
[SIZE &encoding-space-size
[MULTIPLE OF &encoding-space-unit]]
[DETERMINED BY &encoding-space-determination]
[USING &encoding-space-reference
[ENCODER-TRANSFORMS &Encoder-transforms]
[DECODER-TRANSFORMS &Decoder-transforms]]
[ENCODED WITH &Known-structure-encodings]
[UNKNOWN IS &Unknown-structure
[ENCODED WITH &Unknown-structure-encodings]]
[VALUE-PADDING
[JUSTIFIED &value-justification]
[PRE-PADDING &value-pre-padding
[PATTERN &value-pre-pattern]]
[POST-PADDING &value-post-padding
[PATTERN &value-post-pattern]]
[UNUSED BITS
[DETERMINED BY &unused-bits-determination]
[USING &unused-bits-reference
[ENCODER-TRANSFORMS &Unused-bits-encoder-transforms]
[DECODER-TRANSFORMS &Unused-bits-decoder-transforms]]]]
[EXHIBITS HANDLE &exhibited-handle AT &Handle-positions
[AS &handle-value]
[BIT-REVERSAL &bit-reversal]
}
23.9 bis.2 Model for the encoding of classes in the open type category
23.9 bis.2.1
The model of open type encodings is:
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
9
ISO/IEC 8825-3:2002/Amd.1:2005 (E)
a)
The class in the open type category can be replaced by another structure to provide length delimitation if
required.
b)
The encoding object defined for this category applies the "ENCODED WITH" encoding object set to the
type whose value is to be encoded for the open type. If there is no "ENCODED WITH", then the current
combined encoding object set is used.
c)
The decoder will request the application for identification of the type encoded into the open type. The
application will either respond with identification of the type, which is then decoded, or will state that the
type encoded in the open type cannot be determined (an "unknown" response).
d)
If the response is "unknown" and the "UNKNOWN IS" is present, then the decoder will use the "UNKNOWN
IS" structure and the "ENCODED WITH" within the "UNKNOWN IS" (if present) to determine the end of the
encoding space.
e)
If the response is "unknown" and the "UNKNOWN IS" is absent, then the encoding space size can be
determined by the "ENCODING-SPACE" (see 23.9 bis.3.3), and the decoder will return to the application
all the bits contained in the defined encoding space except for value pre- and post-padding.
23.9 bis.2.2 In the case of an unknown decoding, the decoder will pass the bits forming the unknown encoding to the
application as the value of the open type.
23.9 bis.3 Purpose and restrictions
23.9 bis.3.1 This syntax is used to define the way an open type is encoded, and the means that a decoder uses to
determine the end of the encoding of an unknown type in an open type.
23.9 bis.3.2
If "REPLACE STRUCTURE" is set no other parameters shall be set.
23.9 bis.3.3
If "ENCODING-SPACE SIZE" is "self-delimiting" then "UNKNOWN IS" shall be set.
23.9 bis.4 Encoder actions
23.9 bis.4.1 For any encoding property group that is set, the encoder shall perform the encoder actions specified in
clause 22, in the following order and in accordance with the encoding object definition:
a)
replacement;
b)
pre-alignment and padding;
c)
start pointer;
d)
encoding space (see 23.9 bis.4.3);
e)
open-type encoding (see 23.9 bis.4.2);
f)
value padding and justification (see 23.9 bis.4.5);
g)
bit reversal.
23.9 bis.4.2 The encoder shall encode the value of the type supplied by the application using the "ENCODED WITH"
encoding object set if this is present, otherwise the current combined encoding object set shall be used.
23.9 bis.4.3 If "ENCODING-SPACE SIZE" is "variable-with-determinant" or "encoder-option-withdeterminant", it shall be the minimum number of "MULTIPLE OF" units needed to contain the pattern ("s", say),
subject to 23.9 bis.4.5.
23.9 bis.4.4 An encoder (as an encoder's option) may increase "s" (as determined in 23.9 bis.4.3) in "MULTIPLE OF"
units (subject to any restrictions that the range of values of any "added-field" or "asn1-field" imposes) if
"ENCODING-SPACE SIZE" is set to "encoder-option-with-determinant".
23.9 bis.4.5 If the number of unused bits is not zero, then "VALUE-JUSTIFICATION" shall be applied using either the
set values or the default values.
23.9 bis.5 Decoder actions
23.9 bis.5.1 For any encoding property group that is set, the decoder shall perform the decoder actions specified in
clause 22, in the following order and in accordance with the encoding object definition:
10
a)
pre-alignment and padding;
b)
start pointer;
c)
encoding space;
d)
bit-reversal;
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
ISO/IEC 8825-3:2002/Amd.1:2005 (E)
e)
value padding and justification;
f)
open-type decoding (see 23.9 bis.5.2).
23.9 bis.5.2 For open type decoding, the decoder shall query the application for the type which has been encoded and
shall decode a value of that type or of the "UNKNOWN IS" structure in accordance with the "ENCODED WITH"
specifications in the "UNKNOWN IS".
23.9 bis.5.3 If the decoding was of an unknown type, the bits forming the unknown encoding (without pre-padding
bits and without value pre- and post-padding bits, if any) shall be passed to the application as the value of the open type.
24
Subclause 23.12.2.3
Replace 23.12.2.3 with:
23.12.2.3 If an encoding object in the "REPETITION-ENCODINGS" ordered list is defined using "IF" or "IF-ALL", then
all preceding encoding objects in that list shall be defined using "IF" or "IF-ALL".
25
Subclause 23.13.1
Replace 23.13.1 with:
23.13.1 The defined syntax
The syntax for defining encoding objects for the #CONDITIONAL-REPETITION class is defined as:
#CONDITIONAL-REPETITION ::= ENCODING-CLASS {
-- Condition (see 21.12)
&size-range-condition
&comparison
&comparator
&Size-range-conditions
&Comparisons
&Comparators
SizeRangeCondition OPTIONAL,
Comparison OPTIONAL,
INTEGER OPTIONAL,
SizeRangeCondition ORDERED OPTIONAL,
Comparison ORDERED OPTIONAL,
INTEGER ORDERED OPTIONAL,
-- Structure or component replacement specification (see 22.1)
&#Replacement-structure
OPTIONAL,
&replacement-structure-encoding-object &#Replacement-structure OPTIONAL,
&#Head-end-structure
OPTIONAL,
-- Pre-alignment and padding specification (see 22.2)
&encoding-space-pre-alignment-unit Unit (ALL EXCEPT repetitions) DEFAULT bit,
&encoding-space-pre-padding
Padding DEFAULT zero,
&encoding-space-pre-pattern
Non-Null-Pattern (ALL EXCEPT different:any)
DEFAULT bits:'0'B,
-- Start pointer specification (see 22.3)
&start-pointer
REFERENCE
OPTIONAL,
&start-pointer-unit
Unit (ALL EXCEPT repetitions) DEFAULT bit,
&Start-pointer-encoder-transforms #TRANSFORM ORDERED OPTIONAL,
-- Repetition space specification (see 22.7)
&repetition-space-size
EncodingSpaceSize
DEFAULT self-delimiting-values,
&repetition-space-unit
Unit DEFAULT bit,
&repetition-space-determination
RepetitionSpaceDetermination
DEFAULT field-to-be-set,
&main-reference
REFERENCE OPTIONAL,
&Encoder-transforms
#TRANSFORM ORDERED OPTIONAL,
&Decoder-transforms
#TRANSFORM ORDERED OPTIONAL,
&handle-id
PrintableString
DEFAULT "default-handle",
&termination-pattern
Non-Null-Pattern (ALL EXCEPT
different:any) DEFAULT '0'B,
-- Repetition alignment
&repetition-alignment
ENUMERATED {none, aligned}
DEFAULT none,
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
11
ISO/IEC 8825-3:2002/Amd.1:2005 (E)
-- Value padding and justification (see 22.8)
&value-justification
Justification DEFAULT right:0,
&value-pre-padding
Padding DEFAULT zero,
&value-pre-pattern
Non-Null-Pattern DEFAULT bits:'0'B,
&value-post-padding
Padding DEFAULT zero,
&value-post-pattern
Non-Null-Pattern DEFAULT bits:'0'B,
&unused-bits-determination
UnusedBitsDetermination
DEFAULT field-to-be-set,
&unused-bits-reference
REFERENCE OPTIONAL,
&Unused-bits-encoder-transforms
#TRANSFORM ORDERED OPTIONAL,
&Unused-bits-decoder-transforms
#TRANSFORM ORDERED OPTIONAL,
-- Identification handle specification (see 22.9)
&exhibited-handle
PrintableString OPTIONAL,
&Handle-positions
INTEGER (0..MAX) OPTIONAL,
&Handle-value
HandleValue DEFAULT tag: any,
-- Bit reversal specification (see 22.12)
&bit-reversal
ReversalSpecification
DEFAULT no-reversal
}
WITH SYNTAX {
[IF &size-range-condition [&comparison &comparator]]
[IF-ALL &Size-range-conditions [&Comparisons &Comparators]]
[ELSE]
[REPLACE
[STRUCTURE]
[COMPONENT]
[ALL COMPONENTS]
WITH &Replacement-structure
[ENCODED BY &replacement-structure-encoding-object
[INSERT AT HEAD &#Head-end-structure]]]
[ALIGNED TO
[NEXT]
[ANY]
&encoding-space-pre-alignment-unit
[PADDING &encoding-space-pre-padding
[PATTERN &encoding-space-pre-pattern]]]
[START-POINTER
&start-pointer
[MULTIPLE OF
&start-pointer-unit]
[ENCODER-TRANSFORMS
&Start-pointer-encoder-transforms]]
REPETITION-SPACE
[SIZE &repetition-space-size
[MULTIPLE OF &repetition-space-unit]]
[DETERMINED BY &repetition-space-determination
[HANDLE &handle-id]]
[USING &main-reference
[ENCODER-TRANSFORMS &Encoder-transforms]
[DECODER-TRANSFORMS &Decoder-transforms]]
[PATTERN &termination-pattern]
[ALIGNMENT &repetition-alignment]
[VALUE-PADDING
[JUSTIFIED &value-justification]
[PRE-PADDING &value-pre-padding
[PATTERN &value-pre-pattern]]
[POST-PADDING &value-post-padding
[PATTERN &value-post-pattern]]
[UNUSED BITS
[DETERMINED BY &unused-bits-determination]
[USING &unused-bits-reference
[ENCODER-TRANSFORMS &Unused-bits-encoder-transforms]
[DECODER-TRANSFORMS &Unused-bits-decoder-transforms]]]]
[EXHIBITS HANDLE &exhibited-handle AT &Handle-positions
[AS &handle-value]]
[BIT-REVERSAL &bit-reversal]
}
12
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
ISO/IEC 8825-3:2002/Amd.1:2005 (E)
26
Subclauses 23.13.2.1 and 23.13.2.2
Replace 23.13.2.1 and 23.13.2.2 with:
23.13.2.1 This syntax is used to define the encoding of a class in the repetition category subject to satisfaction of a
condition based on the bounds of the repetition (use of "IF"). It also allows the specification that all of a set of
conditions are to be satisfied (use of "IF-ALL"). It also allows the specification that there is no condition. The use of
"ELSE", or omission of both "IF", "IF-ALL" and "ELSE" specifies that there is no condition. "IF-ALL" shall be used
with three lists if one or more of the size-range-conditions require a comparison, and shall be used with one list
otherwise. When using three lists, size-range-conditions that do not require a comparison or comparator (if any) shall
follow all those that require a comparison, and shall have no corresponding entry in the second and third lists. In using
"IF-ALL" with three lists, the lists shall be interpreted as a list of predicates using the values in corresponding positions
in the three lists.
NOTE – It is recommended that the three lists be formatted to provide a condition in each column (see the example in 23.7.2.2).
23.13.2.2 At most one of "IF", "IF-ALL" and "ELSE" shall be present.
27
Subclause 23.15
Replace 23.15 with:
23.15
Defining encoding objects for classes in the other categories
In this version of this Recommendation | International Standard, there is no defined syntax for classes in the following
categories:
objectidentifier
open-type
real
28
Subclause 24.3.1
Replace 24.3.1 with:
24.3.1
The int-to-int transform uses the following encoding property:
&int-to-int
29
CHOICE
{increment
decrement
multiply
divide
negate
modulo
subtract
mapping
} OPTIONAL
INTEGER (1..MAX),
INTEGER (1..MAX),
INTEGER (2..MAX),
INTEGER (2..MAX),
ENUMERATED{value},
INTEGER (2..MAX),
ENUMERATED{lower-bound},
IntegerMapping
New subclause 24.3.2 bis
Add new subclause 24.3.2 bis after 24.3.2:
24.3.2 bis The definition of the type used in the int-to-int transform is:
IntegerMapping ::= SET OF SEQUENCE {
source
SET OF INTEGER,
result
INTEGER} (CONSTRAINED BY {/* the intersection of the source
components shall be empty
(see 21.16) */})
30
New subclause 24.3.8 bis
Add new subclause 24.3.8 bis after 24.3.8:
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
13
ISO/IEC 8825-3:2002/Amd.1:2005 (E)
24.3.8 bis The transform for the value "mapping:integerMapping" is defined as follows. The original integer value
is replaced with the value associated to the set of values to which it belongs. It is an ECN specification error if the
intersection of the sets of values is not empty; it is an application error if the original integer does not belong to one of
the value sets.
31
Table 6
Add the following row to the end of Table 6:
mapping:integerMapping
32
Source value sets, each containing only
one value, and the result values are
distinct.
Subclause C.1
Replace the "Governor" production in C.1 with the following:
Governor ::=
|
|
|
|
33
EncodingClassFieldType
REFERENCE
DefinedOrBuiltinEncodingClass
#ENCODINGS
Type
Subclause C.4
Replace C.4 with the following:
C.4
Actual parameter list
ITU-T Rec. X.683 | ISO/IEC 8824-4, 9.5, is modified as follows:
9.5
The "ActualParameterList" is:
ActualParameterList ::=
"{<" ActualParameter "," + ">}"
ActualParameter ::=
Value
|
ValueSet
|
OrderedValueList
|
DefinedOrBuiltinEncodingClass
|
EncodingObject
|
EncodingObjectSet
|
OrderedEncodingObjectList
|
identifier
|
ComponentIdList
|
STRUCTURE
|
OUTER
If the corresponding dummy parameter is:
14
a)
a value: the "Value" alternative shall be used;
b)
a value set: the "ValueSet" alternative shall be used;
c)
a fixed-type ordered value list: the "OrderedValueList" alternative shall be used;
d)
an encoding class: the "DefinedOrBuiltinEncodingClass" alternative shall be used;
e)
an encoding object: the "EncodingObject" alternative shall be used;
f)
an encoding object set: the "EncodingObjectSet" alternative shall be used;
g)
an ordered encoding object list: the "OrderedEncodingObjectList" alternative shall be used;
h)
a reference: the "identifier""ComponentIdList", STRUCTURE or OUTER alternative shall be used.
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
ISO/IEC 8825-3:2002/Amd.1:2005 (E)
STRUCTURE shall only be used when the actual parameter is used as specified in 17.5.15. OUTER can be used whenever a
reference is required to identify a container, and identifies the container of the entire encoding.
34
Subclause G.2.4
Replace the "Governor" production in G.2.4 with the following:
Governor ::=
|
|
|
|
EncodingClassFieldType
REFERENCE
DefinedOrBuiltinEncodingClass
#ENCODINGS
Type
ITU-T Rec. X.692 (2002)/Amd.1 (08/2004)
15
SERIES OF ITU-T RECOMMENDATIONS
Series A
Organization of the work of ITU-T
Series D
General tariff principles
Series E
Overall network operation, telephone service, service operation and human factors
Series F
Non-telephone telecommunication services
Series G
Transmission systems and media, digital systems and networks
Series H
Audiovisual and multimedia systems
Series I
Integrated services digital network
Series J
Cable networks and transmission of television, sound programme and other multimedia signals
Series K
Protection against interference
Series L
Construction, installation and protection of cables and other elements of outside plant
Series M
TMN and network maintenance: international transmission systems, telephone circuits,
telegraphy, facsimile and leased circuits
Series N
Maintenance: international sound programme and television transmission circuits
Series O
Specifications of measuring equipment
Series P
Telephone transmission quality, telephone installations, local line networks
Series Q
Switching and signalling
Series R
Telegraph transmission
Series S
Telegraph services terminal equipment
Series T
Terminals for telematic services
Series U
Telegraph switching
Series V
Data communication over the telephone network
Series X
Data networks and open system communications
Series Y
Global information infrastructure, Internet protocol aspects and Next Generation Networks
Series Z
Languages and general software aspects for telecommunication systems
*27070*
Printed in Switzerland
Geneva, 2005